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Some I m p o r t a n t Features of The Beckman Model H F u l l A C O p e r a t i o n ζ The Model Η is completely self-contained and operates directly f r o m standard 115 volt A C lines v/ithowt accessory equipment of a n y kind. H i g h A c c u r a c y : The accuracy of the Model Η instrument is equivalent to that of the w e l l known Model M and Model G Beckman pH Meters. For r a p i d work, accuracies of 0.1 pH unit a r e easily obtained, and m o r e careful attention to technique permits determinations to 0.02 pH units. Such high accuracy has never b e fore been available in a compact AC p H Meter.
The First Portable AC p H Meter with DC Accuracy, Simplicity and Dependability
Single-Point Buffer Calibrations: With the Beckman Model H it is not necessary to calibrate with two buffer solutions. The Model H incorporates a unique electronic circuit that permits a c curate readings regardless of variations in resistance of the glass electrodes due to aging o r due to electrode temperature changes after calibrations. This important advantage is accomplished with out need for multiple b u f f e r calibrations.
TO LONGER n e e d you. sacrifice accuracy a n d de p e n d a b i l i t y t o get t h e c o n v e n i e n c e o f AC o p e r a t i o n in a portable p H Meter. For n o w t h e s a m e o r g a n i z a t i o n that p i o n e e r e d m o d e r n glass electrode p H e q u i p m e n t , and has p i o n e e r e d e v e r y m a j o r a d v a n c e m e n t i n m o d e r n pfl i n s t r u m e n t a t i o n and m e t h o d s , brings a n o t h e r im portant d e v e l o p m e n t . . . a p o r t a b l e pH M e t e r that oper ates f r o m standard AC c u r r e n t without sacrificing any of the accuracy and dependability that are so essential in modern pH applications.
M a x i m u m T e m p e r a t u r e S t a b i l i t y : After a short warm-up period, subsequent c h a n g e in calibration of the instrument due t o temperature effects is v e r y small—only about 0.1 pH unit in the first two hours and 0.05 unit subsequently. When maximum accuracy is required, this change m a y be instantly checked and corrected with' out rechecking against buffer solution.
Full Temperature Compensation, 0 fo 10O°C: A builtin temperature compensator covering the full range o f O ° t o 100° C can be set to compensate automatically the effect o f temperature changes on the EMF of t h e glass electrode over the entire p H range of the instrument. Thus, t h e p H a t t h e electrode temperature m a y b e read directly from the d i a l without calculation or corrections.
T h i s new instrument—the Beckman. Model Η p H Meter— h a s been in development over a long period of time. Many different designs and circuits were tested and rejected before a n instrument was perfected that m e e t s the rigid Beckman standards o f excellence. T h e Model Η Meter is not just an CCAC" p H Meter. It is an instrument embodying ad vancements in circuit design that insure the same high oper ating efficiency and accuracy that h a v e made Beckman pH Equipment standard throughout the world.
D i r e c t M i l l i v o l t S c a l e : The Model H Meter is graduated i n millivolts as well as pH u n i t s , and a range switch permits measuring] directly either in millivolts o r pH at will.
Rugged Light w e i g h * Construction: The Model H is housed in a cast aluminum case w i t h an attractive dark g r a y wrinkle finish. The instrument weighs approximately 10 pounds, complete, and is easily carried. For maximum operating convenience the meter d i a l and all controls a r e mounted on a sjoping panel.
A few of the many unique features incorporated into the Beckman Model H pH Meter are outlined at right. Con tact your nearest distributor o f Beckman p H Instruments for further details... o r write direct. Beckman Instruments, îiational Technical Laboratories, South Pasadena, Calif·
RUMENTS V O L U M E
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INDUSTRB1 2545
